Sequential turbo setup in a Scion FR-S

[FR_S_Fan]

I want to see what everyone thinks about having a sequential turbo setup in the FR-S from factory/aftermarket world. Doing a single turbo setup is very common but with gas prices you really need to find the medium between fuel efficiency and enough power and having a turbo only makes your heavy foot problem a lot worse. Turbo lag is also an issue.

Sequential turbo setup's are better depending how you look at it. The big plus is having little to no turbo lag!

The BMW 335i comes with a sequential turbo setup from factory and every 335i owner I spoke to had nothing but good things to say about it.

I think having a FR-S sequential turbo setup from factory will achieve a lot of goals such as fuel efficiency with the help of the smaller turbo and big power when needed with the large turbo.

Discuss...

[Enzie]

sounds good but i think it would drive up the price if it came stock on the car

[levin]

controlling and managing two different sized turbos is no easy task. especially in a 4 cylinder. The turbos would have to run in series causing some pretty strange pressure issues to the exhaust housings in the turbos. And if you run them parallel you might not have enough space for all the piping. Too complicated.

[Shadowkilla510]

Correct me if I'm wrong, but I'm sure there is a thread on this forum site that talks about how the engine is naturally aspirated rather than turbo? And I've also heard that the compression rate of the engine is too high for a turbo and if one was to put on a turbo, then the engine would get all messed up. About fuel efficiency, honestly if Kia could make a 272 hp turbo engined car, that looks good by the way, get between 22-24 city mpg then I'm sure Toyota and Scion could figure something out as well.

[cfrp]

for the amount of boost pressure (not very much) that manufacturers run on OEM turbo setups the compression isn't too much of an issue. As long as the block is built strong it'll handle the pressure. What causes issues with sequential turbos is when the pressures from the two turbos are different and they cause problems with each other. When one turbo has issues it effects the tuning. Tuning two different sized turbos is a tricky task. You better make sure you have two very reliable turbos.

[FR_S_Fan]

Correct me if I'm wrong, but I'm sure there is a thread on this forum site that talks about how the engine is naturally aspirated rather than turbo?

There sure is, but were talking about the possibility of something like this. It may not happen but something to consider.

And I've also heard that the compression rate of the engine is too high for a turbo and if one was to put on a turbo, then the engine would get all messed up. About fuel efficiency, honestly if Kia could make a 272 hp turbo engined car, that looks good by the way, get between 22-24 city mpg then I'm sure Toyota and Scion could figure something out as well.

I wasn't aware of the compression on the FR-S engine, but it's likely a turbo can mess up the engine if compression isn't to what is needed. Toyota and Scion is building this car with tuners in mind, I would imagine the engineers at Toyota are considering a turbo setup or building the engine in such a way the addition of a turbo (aftermarket) with proper tuning will work well.

[import_nation]

turbocharging isn't going to be impossible. it will work with money.

[FR_S_Fan]

turbocharging isn't going to be impossible. it will work with money.

This is true, hopefully the FR-S engine won't need crazy amounts of engine modifications to support a decent turbo upgrade. If Toyota now is anything like it's past with bulletproof motor's that come N/A (2JZ-GE) but handle track worthy turbo kit's the FR-S should be a big hit.

[AE86]

Keep in mind this isn't a Toyota Designed motor, the idea was borrowed from Subaru, and just because they made one bullet proof engine doesn't mean that all their motors are bullet proof.

Also doubt they will have a Sequential turbo set-up on the Subaru's... In north america the Subaru here are set-up with a single turbo design, the JDM turbos are set up for a twin turbo twin scroll design.

Also setting a tune and a map for a sequential turbo is a pain in the ass! lol

[import_nation]

Both Toyota and Subaru performance engines are known to handle boost quite well. I don't think the FR-S is going to have trouble. Stop being negative people. POSITIVE THINKING

[FR_S_Fan]

Both Toyota and Subaru performance engines are known to handle boost quite well. I don't think the FR-S is going to have trouble. Stop being negative people. POSITIVE THINKING

I am expecting the FR-S engine to be really good, maybe not "bullet proof" status since we will have to test it seriously to label it that.

Since the FR-S is being built with racing in mind, the FR-S engine should be able to handle a lot of abuse. Tuning the engine will be a whole different world, especially if your going for forced induction.